Current external fixation technology includes two main groups of devices: static fixation systems and hinged fixation systems. Static external fixation has been used in the upper limb for decades, including the elbow. A drawback with static external fixation is that the joint becomes stiff without motion. The fixator systems for static application can also be difficult to dismantle and reassemble for post-operative mobilization. Therefore, once applied, these static fixation systems can lead to more stiffness and suboptimal results.
Existing hinged devices include a single joint axis that can be unlocked so that the arm can be flexed and extended while the external fixator remains connected to the humerus and ulna. These external hinged devices are challenging to apply and, unless used on a frequent basis, can require long operative time. In order to match the hinge axis of the fixator to the hinge axis of the elbow joint, fluoroscopy is used, or a pin is driven directly through the axis of the joint. It is difficult to precisely place this axis. If the alignment is suboptimal, the device may bind and lead to more limited motion or worse, joint subluxation. In an emergency setting, the requisite skilled personnel and equipment may not be available. The complexity of these devices leads to a general reluctance to use them, even in patients that require some form of external fixation. This can result in inadequate treatment, secondary referrals, and/or subsequent poor outcomes.
Accordingly, it would be desirable to provide a device that allows for a simplified device application and the ability to maintain joint motion.